ABSTRACT
BACKGROUND: The (H1N1)pdm09 live attenuated influenza vaccine (LAIV) strain was changed for the 2017-2018 influenza season to improve viral fitness, following poor protection against (H1N1)pdm09 viruses in 2015-2016. We conducted LAIV virus shedding studies to assess the effect of this change. METHODS: Children aged 2-18 years were recruited to receive LAIV in the 2016-2017 (n = 641) and 2017-2018 (n = 362) influenza seasons. Viruses from nasal swabs taken 1, 3, and 6 days postvaccination were quantified by reverse-transcription polymerase chain reaction and area under the curve titers were determined. Presence and quantity of shedding were compared between strains and seasons with adjustment for age and prior LAIV (n = 436), inactivated seasonal vaccine (n = 100), or (H1N1)pdm09 vaccine (n = 166) receipt. RESULTS: (H1N1)pdm09 detection (positivity) in 2016-2017 and 2017-2018 (11.2% and 3.9%, respectively) was lower than that of H3N2 (19.7% and 18.7%, respectively) and B/Victoria (28.9% and 33.9%, respectively). (H1N1)pdm09 positivity was higher in 2016-2017 than 2017-2018 (P = .005), but within shedding-positive participants, the (H1N1)pdm09 titer increased in 2017-2018 (P = .02). H3N2 and influenza B titers were similar between seasons. Positivity declined with age, and prior vaccination reduced the likelihood of shedding influenza B but not (H1N1)pdm09. CONCLUSIONS: The (H1N1)pdm09 titer increased in 2017-2018, indicating more efficient virus replication in shedding-positive children than the 2016-2017 strain, although overall positivity was reduced. Age and vaccination history require consideration when correlating virus shedding and protection. CLINICAL TRIALS REGISTRATION: NCT02143882, NCT02866942, and NCT03104790.
Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Adolescent , Child , Child, Preschool , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H3N2 Subtype/genetics , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Seasons , United Kingdom/epidemiology , Vaccines, Attenuated , Virus SheddingABSTRACT
AIM: Irritable bowel syndrome (IBS) is a common disorder and many patients fail to find adequate relief from conventional therapies for their symptoms. This study tests the claim that acupuncture is effective for a majority of these patients. METHODS: A prospective, blinded, sham acupuncture-controlled trial of traditional Chinese acupuncture was performed at a single postgraduate teaching hospital in Europe. Sixty patients with well-established IBS were recruited. The blinded comparator was sham acupuncture administered by the second of two acupuncturists who alone was aware of the randomization, and who otherwise followed the prescription of the first. The primary end-point was a defined fall in the symptom score at 13 wk (by intention to treat). The prior expectation was a 30% placebo response, and a response rate of 70% from acupuncture, for which the study was adequately powered. RESULTS: Patients in treated and sham groups improved significantly during the study-mean improvement in scores being equal (minus 1.9) and significant for both (P<0.05; one-tailed t test). There was a small numeric but non-significant difference between the response rate in patients receiving acupuncture (40.7%) and sham treatment (31.2%). Several secondary end-points marginally favored active treatment, but an improved symptom score of any degree of magnitude occurred more often with sham therapy (65.6% vs 59.2%). For no criterion was statistical significance approached. CONCLUSION: Traditional Chinese acupuncture is relatively ineffective in IBS in the European hospital setting, and the magnitude of any effect appears insufficient to warrant investment in acupuncture services.